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Dry air from my air compressor?

Discussion in 'Gen 2 Prius Main Forum' started by ChrisHenry, Nov 6, 2007.

  1. ChrisHenry

    ChrisHenry New Member

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    Reading the "Nitrogen in the tires" thread tonight made me wonder about how I can get dry air into (and out of) my air compressor.

    I have a consumer-grade air compressor that's bigger than the little pancake ones, but still small enough to be easily portable. Is there some type of filter or mechanism that can remove moisture from the air going into the tank?

    I live in southern California near sea level, so there's definitely moisture in the air.

    Do I really need to worry about this? Should I just take the car into the tire shop for periodic refills?
     
  2. Tom_06

    Tom_06 Active Member

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    <div class='quotetop'>QUOTE(Chris Henry @ Nov 6 2007, 12:11 AM) [snapback]535307[/snapback]</div>
    SCUBA compressors use a device called a moisture separator. Should be able to fit one on your compressor. May need an oil filter before it to keep oil in the output air from killing the moisture separator's elements.

    - Tom
     
  3. Tom_06

    Tom_06 Active Member

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    <div class='quotetop'>QUOTE(Tom_06 @ Nov 6 2007, 05:55 AM) [snapback]535389[/snapback]</div>
    Here's a reasonably cheap one. Probably not up to breathable-air standards like SCUBA units:

    http://www.amazon.com/D55023-Heavy-Duty-Co...r/dp/B0008GLWA8

    - Tom
     
  4. qbee42

    qbee42 My other car is a boat

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    Water separators are also used for most air operated tools, as it's not good for them to have water injected into their working parts, and water is bad for most spray painting operations. Any good tools supply place will have them.

    Tom
     
  5. viking31

    viking31 Member

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    <div class='quotetop'>QUOTE(Tom_06 @ Nov 6 2007, 08:59 AM) [snapback]535414[/snapback]</div>
    No offense to Tom ;-), but these type of moisture separators are practically useless. They may remove some visible moisture and perhaps a little humidity, but really will not reduce the humidity of the air to any appreciable level. The only real way to remove most of the humidity from air is either using a desiccant type of system (which requires periodic replacement of the desiccant) or use a refrigeration unit (maintenance free) designed for the purpose. Factories which run machines that depend on solenoid valves and such use such devices (unless you like troubleshooting machines for faulty valves on a regular basis! I learned that the hard way!).

    I am always amazed by the claims made by N2 proponents regarding nitrogen fills. Some posters on PC even claim 20% mileage increases when using N2 vs. standard air! Automobile tires (esp. the Prius) just do not have the temperature differences under normal driving conditions to justify the extra expense to fill with special or dehumidified gases.

    Rick
    #4 2006
     
  6. skguh

    skguh Member

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    I wonder if condensation increases as the air inside the tires differs from the heat generated by the friction of the tires as they heat up and cool down....

    What's next? Glade tire freshener?
     
    bisco likes this.
  7. qbee42

    qbee42 My other car is a boat

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    <div class='quotetop'>QUOTE(viking31 @ Nov 6 2007, 12:29 PM) [snapback]535528[/snapback]</div>
    Agreed. The water separators aren't useless, but mostly they remove liquid water, which otherwise will work it's way into the hoses and eventually to the tools or sprayers. Rick is correct that to really dry air requires more sophisticated equipment. Some of the desiccant systems can be recharged through heating, although this can be a bother.

    Tom


    <div class='quotetop'>QUOTE(skguh @ Nov 6 2007, 02:58 PM) [snapback]535627[/snapback]</div>
    Condensation is increased because a volume of moist air is compressed into a smaller volume. The compressed volume still contains the same amount of water, but in a smaller volume. The smaller volume of air can hold a smaller amount of water as vapor at a given temperature, meaning the water is more likely to condense.

    Tom
     
  8. bisco

    bisco cookie crumbler

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